“Now I need to take away 324, which is the subtrahend. In 548, I have 5 hundreds, 4 tens, and 8 ones.” As you are saying this, get five flats, four longs, and eight cubes. Remember, ‘minuend’ means the number from which another number is subtracted. “I am going to model how I can use base-ten blocks to find the difference of these two numbers. “Not only can we use base-ten blocks to find the sum of two numbers, we can also use base-ten blocks to find the difference of two numbers.” Write 548 – 324 = on the board. Have a student show the class what s/he did on his/her whiteboard. “Now, on your whiteboard please show me what this addition problem would look like if you drew pictures of base-ten blocks rather than using the actual base-ten blocks.” Support students as they find the sum by drawing pictures of base-ten blocks rather than using the actual blocks. Have a student show the class what s/he did and write the sum after the equals sign. Support students as they find the sum of these two numbers. Ask students to use their base-ten blocks to solve this equation. Write the equation 458 + 123 = on the board. Have a student show the class what s/he did and write the sum after the equal sign. How many hundreds do we need? (2) How many tens do we need? (2) How many ones do we need? (2) Please use your base-ten blocks to find the sum of these two numbers.” Support students as they find the sum of these two numbers. How many hundreds do we need? (2) How many tens do we need? (5) How many ones do we need? (7) Now we need to make 222. Write the problem 257 + 222 = on the board. Now, show students what the above problem would look like using pictures of base-ten blocks rather than the actual base-ten blocks.ĭistribute base-ten blocks to each student. A square represents a flat, a vertical line represents a long, and a dot represents a cube. Remind students how to draw base-ten blocks. “Now I can join the base-ten blocks and count them to find the sum of 231 + 146.” Model by putting the flats together, the longs together, the cubes together, and then counting the base-ten blocks. “In the number 146 I have 1 hundred, 4 tens, and 6 ones.” As you are saying this, get one flat, four longs, and six cubes. In the number 231 I have 2 hundreds, 3 tens, and 1 one.” As you are saying this, get two flats, three longs, and one cube. “I am going to model how I can use base-ten blocks to find the sum of these two numbers. Write the problem 231 + 146 = on the board. It represents 10.” Hold up a cube and say, “This is a cube. It represents 100.” Hold up a long and say, “This is a long. “Today we are going to add and subtract two- and three-digit numbers using base-ten blocks.” Students move from using base-ten blocks to using pictures of base-ten blocks to add and subtract three-digit numbers. The lesson was designed to help students gain a better understanding of adding and subtracting three-digit numbers. The lesson may be tailored using the suggestions in the Extension section. Use the Adding and Subtracting Using Base-Ten Blocks Worksheet and the responses to questions throughout the lesson to determine student understanding of using base-ten blocks to add and subtract three-digit numbers. The questions asked before, during, and after the lesson will cause students to reflect on their understanding of using base-ten blocks to add and subtract three-digit numbers. Students will add and subtract three-digit numbers using base-ten blocks. Inform students that they will be using these materials to help them add and subtract three-digit numbers. Inform them that base-ten blocks can be helpful in adding and subtracting three-digit numbers.ĭisplay the base-ten blocks. Inform students that our system for writing numbers is called the base-ten system because it is based on grouping things by tens. Scaffolding, Active Engagement, Modeling, Explicit Instruction W:
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |